Called WhistleGPS, this rugged gadget, about the size of a silver dollar, attaches to a dog's collar to monitor how much activity it gets in a day, as well as give the owner GPS information about the dog's location.

The new device will sell for $129, the same price as the previous Whistle, with a monthly GPS service of only $5. If you pre-order the WhistleGPS soon, you can get it for just $49, which is a serious bargain.

Let me come clean and say that I used to be a complete skeptic about dog activity monitors. No, I was more than skeptical. I scoffed at the idea that you might hang a fitness tracker on a dog's collar to see how much exercise your pet gets. What a waste of money, I thought.

Then I actually tested the Whistle on my lazy Pekingese and had an ah-ha moment. The value of the device is in getting updates when I wasn't home so I could know exactly when and for how long another pet caretaker walked my little Midgie. When I left town for the day and asked my sister to swing by and take the dog out, I was able to check the Whistle mobile app and see when she did—and if she didn't, I could remind her.

The reason I saw updates throughout the day is because the Whistle syncs via Wi-Fi and Bluetooth. Other pet activity monitors I've seen only sync via Bluetooth, which means you physically have to be near your dog to get updates about her activity. If you're gone for the day (or a few days), you can't get new information. Because Whistle also uses Wi-Fi syncing, you can get updates periodically, as long as your pet is within the vicinity of the route to which you've paired the device.

GPS data was the one big missing feature from the Whistle. Pet owners want a way to track down a lost dog as easily as they can find a missing iPhone with Find My iPhone. Sure, putting a microchip in your pet definitely helps reunite lost dogs with their owners, but only if the dog is found and brought to a facility, such as a veterinarian's office, that can scan the chip. But if your dog is roaming the neighborhood or some nearby woods, wouldn't you like to be able to identify exactly where? You'll be able to do just that with the WhistleGPS and the Whistle mobile app.

So, as silly as a pet activity tracker may sound, the WhistleGPS actually sounds like a very useful device, and certainly well worth $49 plus $5 per month, especially if you have a dog that might accidentally wander too far away from your home or yard. The only downside is that pre-ordered WhistleGPS units won't start shipping until 2015.

Jill Duffy is a contributing editor, specializing in productivity apps and software, as well as technologies for health and fitness. She writes the weekly Get Organized column, with tips on how to lead a better digital life. Her first book, Get Organized: How to Clean Up Your Messy Digital Life is available for Kindle, iPad, and other digital formats. She is also the creator and author of ProductivityReport.org.
Before joining PCMag.com, she was senior editor at the Association for Computing Machinery, a non-profit membership organization for...
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